The method for oxidation of mercaptan in a kind of petroleum cuts
The present invention relates to the method for oxidation of mercaptan in a kind of petroleum cuts, exactly, is the method for oxidation of mercaptan in a kind of petroleum cuts of working load shaped metal phthalocyanine catalyst.
Mercaptan is present in the petroleum productss such as gasoline, kerosene, rocket engine fuel widely.The existence of mercaptan not only makes oil product produce stench, and the stability of oil product is descended, and mercaptan itself also has corrodibility.Therefore, remove the mercaptan in the oil product or by catalyzed oxidation mercaptan is converted into disulphide by extracting and be very important, this process is commonly called deodorization in petroleum refining industry.The at present industrial a kind of deodour method that generally adopts is the Merox catalyzed oxidation technology of American UOP company exploitation.This technology is in liquid base (mainly referring to caustic alkali) medium, is catalyzer with sulfonated phthalocyanine cobalt or poly-phthalocyanine cobalt, under the effect of aerial oxygen, the mercaptan oxidation in the oil product is become disulphide.The shortcoming of this technology is to add liquid base, has the separation and the emission problem of waste lye, is unfavorable for environment protection.
In order to overcome above-mentioned shortcoming, American UOP company has developed a kind of catalyzer again and has used the deodorizing technology (US5,286,372) of this catalyzer.This catalyzer is made of a kind of solid alkali loaded metal title complex, and metal complexes is metal phthalocyanine preferably, and solid alkali can be solid solution, stratiform dihydroxide or their mixture of metal oxide.Use the deodorizing technology of this catalyzer need not add liquid base, needed alkalescence is provided by the solid alkali carrier in the reaction process.
The objective of the invention is on the basis of existing technology, providing a kind of is the method for oxidation of mercaptan in the petroleum cuts of support of the catalyst with the novel solid base material.
Method for oxidation provided by the invention is in the presence of oxygen, with petroleum cuts and catalytic amount be that the metal phthalocyanine catalyst of carrier contacts with the nitrogenize aluminum phosphate, react.
Specifically, method for oxidation provided by the invention is in the presence of oxygen, is 20~100 ℃ in temperature, and preferred 30~60 ℃, liquid hourly space velocity is 1~8h
-1, preferred 1~4h
-1Condition under, with mercaptan and catalytic amount be that the metal phthalocyanine catalyst of carrier contacts with the nitrogenize aluminum phosphate, react.
The source of used oxygen can be the air or oxygen that feeds, and also can be natural dissolved oxygen in the oil product.Extra if desired bubbling air, the pressure of air can be 1~7kg/cm
2, preferred 1~5kg/cm
2But, because the mercaptans content in the petroleum cuts is lower, dissolved oxygen can satisfy the needs of mercaptan oxidation substantially in the oil product of depositing naturally, therefore, and generally speaking needn't extra again aerating oxygen or air.
In order to improve activity of such catalysts, method provided by the invention can also be carried out in the presence of polar compound, and this polar compound can be one of water or low-carbon alcohol, or the mixture of the two arbitrary proportion, wherein low-carbon alcohol particular methanol or ethanol.The content of polar compound in pending distillate is between 10~10000ppm.
Used catalyzer is to be carrier with the nitrogenize aluminum phosphate in the inventive method, 0.1~8.0% of supported catalyst gross weight, and preferred 0.5~5.0% metal phthalocyanine constitutes.
P/Al mol ratio in the said nitrogenize aluminum phosphate is between 0.75~1.50, and is preferred 0.75~1.0, and nitrogen content is 2.5~22 heavy %, preferred 3.5~20 heavy %, and specific surface is 150~450m
2/ g, preferred 200~400m
2/ g.
Said metal phthalocyanine is a phthalocyanine cobalt class title complex, one or both mixtures in the sulfonate of promptly poly-phthalocyanine cobalt or phthalocyanine cobalt, carboxylate salt, the quaternary ammonium salt, and the sulfonate of preferred phthalocyanine cobalt is sulfonated phthalocyanine cobalt.
Said nitrogenize aluminum phosphate is reference literature Appl.Catal.A114, the reported method preparation of L191 (1994) institute, that is, and with quantitative aluminum chloride (AlCl
36H
2O) be dissolved in quantitative phosphoric acid (H
3PO
4) in the solution, making the P/Al mol ratio is 0.75~1.50.Solution is remained on 0~25 ℃, stir and slowly drip propylene oxide down, the mole number of used propylene oxide is 2~10 times of aluminum oxide.After a period of stabilisation, in the room temperature standing over night.After the fragmentation of gained clear gel, drying, be warming up to 650~800 ℃ of roastings 4~24 hours, obtain amorphous phosphoric acid aluminium.The amorphous phosphoric acid aluminium of gained is placed stainless steel reactor, be warming up to 650~800 ℃, feed pure ammonia and carry out nitrogenizing reaction.Ammonia flow is 100~500ml/min, and nitridation time is 3~70 hours.
Said Preparation of catalysts is conventional pickling process, is about to phthalocyanine cobalt class title complex and is dissolved in the mixing solutions of methyl alcohol and ethanol-ammonia, repeatedly floods to the whole suppressed by vector absorptions of solution with the nitrogenize aluminum phosphate then.Each dipping 2~24 hours all through vacuum-drying, was generally 2~24 hours behind each dipping time of drying.
Mercaptan oxidation method in the petroleum fractions provided by the invention owing to use novel solid base material phosphorus nitride acid aluminium as support of the catalyst, during mercaptan in the petroleum oxidate cut, need not add liquid base and can have higher active and stable.
Fig. 1 is when using mercaptan oxidation method provided by the invention, and the mercaptan sulfur content in the jet fuel is curve over time.
The present invention will be further described below in conjunction with embodiment and accompanying drawing.
In each embodiment and Comparative Examples, used raw material all is commercially available chemically pure reagent except that specifying.
Embodiment 1~3
This group embodiment is the preparation of solid alkaline material nitrogenize aluminum phosphate, and this preparation process is reference literature Appl.Catal.A114, and L191 (1994) institute reported method is carried out.
Aluminum chloride (AlCl with 100 grams
36H
2O) be dissolved in 414ml1M phosphoric acid (H
3PO
4) in the solution, solution is remained on 0 ℃, stir slow down overflowing and drip propylene oxide, the amount of used propylene oxide is 6 times of aluminum chloride mole number.After a period of stabilisation, in the room temperature standing over night.With the fragmentation of gained clear gel, after 120 ℃ of dryings, be warming up to 800 ℃ of roastings 12 hours, obtain amorphous phosphoric acid aluminium.
The amorphous phosphoric acid aluminium of gained is placed stainless steel reactor, press reaction conditions shown in the table 1, be warming up to 650~800 ℃, feed pure ammonia and carry out nitrogenizing reaction.Ammonia flow is 100~500ml/min, and nitridation time is 3~70 hours.So can obtain nitrogenize aluminum phosphate series of samples, essential property is as shown in table 1.Nitrogen and P/Al are than measure specific surface low temperature nitrogen determination of adsorption method with X-ray electric spectrum (XPS) method in the table 1.
Table 1
| Sample | Temperature, ℃ | Time, hr | Ammonia flow, ml/min | Nitrogen content, heavy % | P/Al, mol/mol | Specific surface, m
2/g
|
| Embodiment 1 | 800 | 2.5 | 480 | 3.5 | 0.92 | 300 |
| Embodiment 2 | 800 | 12 | 480 | 10.0 | 0.76 | 291 |
| Embodiment 3 | 800 | 24 | 480 | 18.0 | 0.75 | 285 |
Embodiment 4~8
This group embodiment is a Preparation of catalysts.
Slowly feed ammonia in ethanol, can obtain containing the ethanolic soln of 0.5 heavy % ammonia after the dissolving, the ethanolic soln that will contain ammonia mixes by 1: 1 volume ratio with methyl alcohol, obtains the mixing solutions of methyl alcohol and ethanol-ammonia.According to the needs of charge capacity, the treated sulfonated phthalocyanine cobalt (being provided by the Shijiazhuang City, Hebei Province refinery) that does not contain insolubles of Different Weight is dissolved in 45ml methyl alcohol and the ethanol-ammonia solution, obtain containing the dipping solution of sulfonated phthalocyanine cobalt.Divide with the 10 nitrogenize aluminum phosphates that make of gram embodiment 1~3 respectively and flood this solution three times, each solution usage 15ml, each dipping finishes through vacuum-drying 8 hours, gained sample plasma emission spectroscopy (ICP) mensuration Co content wherein, thereby calculate the charge capacity of sulfonated phthalocyanine cobalt in the catalyzer, the results are shown in Table 2.
Table 2
| Embodiment | The solid alkali carrier | Phthalocyanine cobalt charge capacity, heavy % |
| 4 | Embodiment 1 | 1.0 |
| 5 | Embodiment 2 | 1.0 |
| 6 | Embodiment 3 | 1.0 |
| 7 | Embodiment 2 | 2.0 |
| 8 | Embodiment 2 | 0.5 |
Comparative Examples 1
It is a kind of according to US 5,286 that this Comparative Examples provides, 372 report institute synthetic solid basic oxides.
With 128g magnesium nitrate (Mg (NO
3)
26H
2O) and 27g aluminum nitrate (Al (NO
3)
39H
2O) mixed dissolution is made into the aqueous solution that the positively charged ion total concn is 1M in the 600ml deionized water.68g potassium hydroxide and 5g salt of wormwood mixed dissolution are made solution in 550ml water.Under agitation above-mentioned two kinds of solution being splashed in the beaker simultaneously, is 50 ℃ in temperature of reaction, and pH value is approximately stirring reaction under 10 the condition.After above-mentioned two solution dropwise, under this temperature of reaction, continue to stir 4 hours, filter then, be washed till filtrate with deionized water and be neutral, and it is dry down at 80 ℃, obtain hydrotalcite-like layered dihydroxide, put it in 500 ℃ the muffle furnace roasting again 8 hours, obtain the Mg/Al mol ratio and be 5.0 solid basic oxide Mg (Al) O5.
Comparative Examples 2
It is the comparative catalyst of carrier that this Comparative Examples provides a kind of solid basic oxide with gained in the Comparative Examples 1.
According to embodiment 4~8 described method for preparing catalyst, preparing the sulfonated phthalocyanine cobalt charge capacity is the catalyzer of 1.0 heavy %, is said comparative catalyst.
Embodiment 9
Present embodiment illustrates the reactive behavior of method for oxidation provided by the invention to bright sulfur alcohol.
In an airtight double glazing flask that has an eudiometer, the catalyzer and the 5ml n-Octanol that respectively 100mg are selected from embodiment 4~6 join in the reaction flask, and reaction system is full of with oxygen, add the 1.0ml octyl mercaptan then, begin reaction.Temperature of reaction is constant in 35.0 ± 0.1 ℃ in reaction process, and vigorous stirring is to guarantee that being reflected at the power school district carries out.The consumption of throughput tracheae record oxygen writes down the degree that reaction is carried out in reaction process, time that speed of response is spent with consumption 8ml oxygen and the average response speed that calculates is represented.
Listed the speed of response of the aluminum phosphate-supported catalyzer of the nitrogenize of using different nitrogen contents in the table 3 and used comparative catalyst's speed of response, the result shows that method for oxidation provided by the invention and the method for using the comparative catalyst are quite active.
Table 3
| Carrier | Embodiment 1 | Embodiment 2 | Embodiment 3 | Mg(Al)O5 |
| Catalyzer | Embodiment 4 | Embodiment 5 | Embodiment 6 | The comparative catalyst |
| Speed of response, ml/min | 1.4 | 1.8 | 2.1 | 2.1 |
Embodiment 10
The present embodiment explanation is used when having the catalyzer of different sulfonated phthalocyanine cobalt charge capacity, the effect of mercaptan oxidation method provided by the invention.The carrier of catalyst system therefor is made by embodiment 2.The mercaptan oxidation reaction is undertaken by the method among the embodiment 9, and evaluation result sees Table 4.
Table 4
| Embodiment | 8 | 4 | 7 |
| The sulfonated phthalocyanine cobalt charge capacity, heavy % | 0.5 | 1.0 | 2.0 |
| Speed of response, ml/min | 0.7 | 1.8 | 3.4 |
Embodiment 11
Present embodiment illustrates method for oxidation provided by the invention active and stable to mercaptan in the petroleum cuts.
Respectively 10ml embodiment 5 is made catalyzer and comparative catalyst pack in the fixed-bed reactor, be heated to after 40 ℃ that to inject boiling range continuously with pump be that 157~230 ℃, mercaptan sulfur content are No. 3 jet fuels of Iran of 100ppm, keeping temperature is 40 ℃, and liquid hourly space velocity is 2.0h
-1, under normal pressure, removing the mercaptan in the oil product, the oxygen that reacts used is the natural dissolved oxygen in the stock oil.The content of mercaptan sulfur is according to the method potentiometric determination of GB1792-88 in the oil product, and evaluation result is seen Fig. 1.The reaction result that the catalyzer that the reaction result that the catalyzer that curve a represents to use embodiment 5 to make in Fig. 1 obtains, curve b are represented to use Comparative Examples 2 to make obtains.
As can be seen from Figure 1, method for oxidation provided by the invention is compared with the method for using the comparative catalyst, has better mercaptan oxidation activity and activity stability.